Harlow's Monkey Experiments

Rhesus infants chose a cloth mother over a wire milk mother, dethroning feeding as the root of attachment.

Specifications & Metrics

Infants separated from real mothers spent most time clinging to a terrycloth surrogate, visiting the wire one only to feed.
The cloth mother served as a secure base for exploration and comfort under fright, anticipating attachment theory.
Harlow's later social-isolation studies produced severe, lasting disturbance and reshaped primate welfare standards.